/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

//
// Access to Zip archives.
//
#include "ZipFile.h"

#define DEF_MEM_LEVEL 8                // normally in zutil.h?

#include <memory.h>
#include <sys/stat.h>
#include <errno.h>
#include <assert.h>

using namespace android;
//
///*
// * Some environments require the "b", some choke on it.
// */
//#define FILE_OPEN_RO        "rb"
//#define FILE_OPEN_RW        "r+b"
//#define FILE_OPEN_RW_CREATE "w+b"
//
///* should live somewhere else? */
//static status_t errnoToStatus(int err)
//{
//    if (err == ENOENT)
//        return NAME_NOT_FOUND;
//    else if (err == EACCES)
//        return PERMISSION_DENIED;
//    else
//        return (status_t)UNKNOWN_ERROR;
//}
//
///*
// * Open a file and parse its guts.
// */
//status_t ZipFile::open(const char* zipFileName, int flags)
//{
//    bool newArchive = false;
//
//    assert(mZipFp == NULL);     // no reopen
//
//    if ((flags & kOpenTruncate))
//        flags |= kOpenCreate;           // trunc implies create
//
//    if ((flags & kOpenReadOnly) && (flags & kOpenReadWrite))
//        return INVALID_OPERATION;       // not both
//    if (!((flags & kOpenReadOnly) || (flags & kOpenReadWrite)))
//        return INVALID_OPERATION;       // not neither
//    if ((flags & kOpenCreate) && !(flags & kOpenReadWrite))
//        return INVALID_OPERATION;       // create requires write
//
//    if (flags & kOpenTruncate) {
//        newArchive = true;
//    } else {
//        newArchive = (access(zipFileName, F_OK) != 0);
//        if (!(flags & kOpenCreate) && newArchive) {
//            /* not creating, must already exist */
//            ALOGD("File %s does not exist", zipFileName);
//            return NAME_NOT_FOUND;
//        }
//    }
//
//    /* open the file */
//    const char* openflags;
//    if (flags & kOpenReadWrite) {
//        if (newArchive)
//            openflags = FILE_OPEN_RW_CREATE;
//        else
//            openflags = FILE_OPEN_RW;
//    } else {
//        openflags = FILE_OPEN_RO;
//    }
//    mZipFp = fopen(zipFileName, openflags);
//    if (mZipFp == NULL) {
//        int err = errno;
//        ALOGD("fopen failed: %d\n", err);
//        return errnoToStatus(err);
//    }
//
//    status_t result;
//    if (!newArchive) {
//        /*
//         * Load the central directory.  If that fails, then this probably
//         * isn't a Zip archive.
//         */
//        result = readCentralDir();
//    } else {
//        /*
//         * Newly-created.  The EndOfCentralDir constructor actually
//         * sets everything to be the way we want it (all zeroes).  We
//         * set mNeedCDRewrite so that we create *something* if the
//         * caller doesn't add any files.  (We could also just unlink
//         * the file if it's brand new and nothing was added, but that's
//         * probably doing more than we really should -- the user might
//         * have a need for empty zip files.)
//         */
//        mNeedCDRewrite = true;
//        result = NO_ERROR;
//    }
//
//    if (flags & kOpenReadOnly)
//        mReadOnly = true;
//    else
//        assert(!mReadOnly);
//
//    return result;
//}
//
///*
// * Return the Nth entry in the archive.
// */
//ZipEntry* ZipFile::getEntryByIndex(int idx) const
//{
//    if (idx < 0 || idx >= (int) mEntries.size())
//        return NULL;
//
//    return mEntries[idx];
//}
//
///*
// * Find an entry by name.
// */
//ZipEntry* ZipFile::getEntryByName(const char* fileName) const
//{
//    /*
//     * Do a stupid linear string-compare search.
//     *
//     * There are various ways to speed this up, especially since it's rare
//     * to intermingle changes to the archive with "get by name" calls.  We
//     * don't want to sort the mEntries vector itself, however, because
//     * it's used to recreate the Central Directory.
//     *
//     * (Hash table works, parallel list of pointers in sorted order is good.)
//     */
//    int idx;
//
//    for (idx = mEntries.size()-1; idx >= 0; idx--) {
//        ZipEntry* pEntry = mEntries[idx];
//        if (!pEntry->getDeleted() &&
//            strcmp(fileName, pEntry->getFileName()) == 0)
//        {
//            return pEntry;
//        }
//    }
//
//    return NULL;
//}
//
///*
// * Empty the mEntries vector.
// */
//void ZipFile::discardEntries(void)
//{
//    int count = mEntries.size();
//
//    while (--count >= 0)
//        delete mEntries[count];
//
//    mEntries.clear();
//}
//
//
///*
// * Find the central directory and read the contents.
// *
// * The fun thing about ZIP archives is that they may or may not be
// * readable from start to end.  In some cases, notably for archives
// * that were written to stdout, the only length information is in the
// * central directory at the end of the file.
// *
// * Of course, the central directory can be followed by a variable-length
// * comment field, so we have to scan through it backwards.  The comment
// * is at most 64K, plus we have 18 bytes for the end-of-central-dir stuff
// * itself, plus apparently sometimes people throw random junk on the end
// * just for the fun of it.
// *
// * This is all a little wobbly.  If the wrong value ends up in the EOCD
// * area, we're hosed.  This appears to be the way that everbody handles
// * it though, so we're in pretty good company if this fails.
// */
//status_t ZipFile::readCentralDir(void)
//{
//    status_t result = NO_ERROR;
//    unsigned char* buf = NULL;
//    off_t fileLength, seekStart;
//    long readAmount;
//    int i;
//
//    fseek(mZipFp, 0, SEEK_END);
//    fileLength = ftell(mZipFp);
//    rewind(mZipFp);
//
//    /* too small to be a ZIP archive? */
//    if (fileLength < EndOfCentralDir::kEOCDLen) {
//        ALOGD("Length is %ld -- too small\n", (long)fileLength);
//        result = INVALID_OPERATION;
//        goto bail;
//    }
//
//    buf = new unsigned char[EndOfCentralDir::kMaxEOCDSearch];
//    if (buf == NULL) {
//        ALOGD("Failure allocating %d bytes for EOCD search",
//             EndOfCentralDir::kMaxEOCDSearch);
//        result = NO_MEMORY;
//        goto bail;
//    }
//
//    if (fileLength > EndOfCentralDir::kMaxEOCDSearch) {
//        seekStart = fileLength - EndOfCentralDir::kMaxEOCDSearch;
//        readAmount = EndOfCentralDir::kMaxEOCDSearch;
//    } else {
//        seekStart = 0;
//        readAmount = (long) fileLength;
//    }
//    if (fseek(mZipFp, seekStart, SEEK_SET) != 0) {
//        ALOGD("Failure seeking to end of zip at %ld", (long) seekStart);
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    /* read the last part of the file into the buffer */
//    if (fread(buf, 1, readAmount, mZipFp) != (size_t) readAmount) {
//        ALOGD("short file? wanted %ld\n", readAmount);
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    /* find the end-of-central-dir magic */
//    for (i = readAmount - 4; i >= 0; i--) {
//        if (buf[i] == 0x50 &&
//            ZipEntry::getLongLE(&buf[i]) == EndOfCentralDir::kSignature)
//        {
//            ALOGV("+++ Found EOCD at buf+%d\n", i);
//            break;
//        }
//    }
//    if (i < 0) {
//        ALOGD("EOCD not found, not Zip\n");
//        result = INVALID_OPERATION;
//        goto bail;
//    }
//
//    /* extract eocd values */
//    result = mEOCD.readBuf(buf + i, readAmount - i);
//    if (result != NO_ERROR) {
//        ALOGD("Failure reading %ld bytes of EOCD values", readAmount - i);
//        goto bail;
//    }
//    //mEOCD.dump();
//
//    if (mEOCD.mDiskNumber != 0 || mEOCD.mDiskWithCentralDir != 0 ||
//        mEOCD.mNumEntries != mEOCD.mTotalNumEntries)
//    {
//        ALOGD("Archive spanning not supported\n");
//        result = INVALID_OPERATION;
//        goto bail;
//    }
//
//    /*
//     * So far so good.  "mCentralDirSize" is the size in bytes of the
//     * central directory, so we can just seek back that far to find it.
//     * We can also seek forward mCentralDirOffset bytes from the
//     * start of the file.
//     *
//     * We're not guaranteed to have the rest of the central dir in the
//     * buffer, nor are we guaranteed that the central dir will have any
//     * sort of convenient size.  We need to skip to the start of it and
//     * read the header, then the other goodies.
//     *
//     * The only thing we really need right now is the file comment, which
//     * we're hoping to preserve.
//     */
//    if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
//        ALOGD("Failure seeking to central dir offset %ld\n",
//             mEOCD.mCentralDirOffset);
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    /*
//     * Loop through and read the central dir entries.
//     */
//    ALOGV("Scanning %d entries...\n", mEOCD.mTotalNumEntries);
//    int entry;
//    for (entry = 0; entry < mEOCD.mTotalNumEntries; entry++) {
//        ZipEntry* pEntry = new ZipEntry;
//
//        result = pEntry->initFromCDE(mZipFp);
//        if (result != NO_ERROR) {
//            ALOGD("initFromCDE failed\n");
//            delete pEntry;
//            goto bail;
//        }
//
//        mEntries.add(pEntry);
//    }
//
//
//    /*
//     * If all went well, we should now be back at the EOCD.
//     */
//    {
//        unsigned char checkBuf[4];
//        if (fread(checkBuf, 1, 4, mZipFp) != 4) {
//            ALOGD("EOCD check read failed\n");
//            result = INVALID_OPERATION;
//            goto bail;
//        }
//        if (ZipEntry::getLongLE(checkBuf) != EndOfCentralDir::kSignature) {
//            ALOGD("EOCD read check failed\n");
//            result = (status_t)UNKNOWN_ERROR;
//            goto bail;
//        }
//        ALOGV("+++ EOCD read check passed\n");
//    }
//
//bail:
//    delete[] buf;
//    return result;
//}
//
//
///*
// * Add a new file to the archive.
// *
// * This requires creating and populating a ZipEntry structure, and copying
// * the data into the file at the appropriate position.  The "appropriate
// * position" is the current location of the central directory, which we
// * casually overwrite (we can put it back later).
// *
// * If we were concerned about safety, we would want to make all changes
// * in a temp file and then overwrite the original after everything was
// * safely written.  Not really a concern for us.
// */
//status_t ZipFile::addCommon(const char* fileName, const void* data, size_t size,
//    const char* storageName, int sourceType, int compressionMethod,
//    ZipEntry** ppEntry)
//{
//    ZipEntry* pEntry = NULL;
//    status_t result = NO_ERROR;
//    long lfhPosn, startPosn, endPosn, uncompressedLen;
//    FILE* inputFp = NULL;
//    unsigned long crc;
//    time_t modWhen;
//
//    if (mReadOnly)
//        return INVALID_OPERATION;
//
//    assert(compressionMethod == ZipEntry::kCompressDeflated ||
//           compressionMethod == ZipEntry::kCompressStored);
//
//    /* make sure we're in a reasonable state */
//    assert(mZipFp != NULL);
//    assert(mEntries.size() == mEOCD.mTotalNumEntries);
//
//    /* make sure it doesn't already exist */
//    if (getEntryByName(storageName) != NULL)
//        return ALREADY_EXISTS;
//
//    if (!data) {
//        inputFp = fopen(fileName, FILE_OPEN_RO);
//        if (inputFp == NULL)
//            return errnoToStatus(errno);
//    }
//
//    if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    pEntry = new ZipEntry;
//    pEntry->initNew(storageName, NULL);
//
//    /*
//     * From here on out, failures are more interesting.
//     */
//    mNeedCDRewrite = true;
//
//    /*
//     * Write the LFH, even though it's still mostly blank.  We need it
//     * as a place-holder.  In theory the LFH isn't necessary, but in
//     * practice some utilities demand it.
//     */
//    lfhPosn = ftell(mZipFp);
//    pEntry->mLFH.write(mZipFp);
//    startPosn = ftell(mZipFp);
//
//    /*
//     * Copy the data in, possibly compressing it as we go.
//     */
//    if (sourceType == ZipEntry::kCompressStored) {
//        if (compressionMethod == ZipEntry::kCompressDeflated) {
//            bool failed = false;
//            result = compressFpToFp(mZipFp, inputFp, data, size, &crc);
//            if (result != NO_ERROR) {
//                ALOGD("compression failed, storing\n");
//                failed = true;
//            } else {
//                /*
//                 * Make sure it has compressed "enough".  This probably ought
//                 * to be set through an API call, but I don't expect our
//                 * criteria to change over time.
//                 */
//                long src = inputFp ? ftell(inputFp) : size;
//                long dst = ftell(mZipFp) - startPosn;
//                if (dst + (dst / 10) > src) {
//                    ALOGD("insufficient compression (src=%ld dst=%ld), storing\n",
//                        src, dst);
//                    failed = true;
//                }
//            }
//
//            if (failed) {
//                compressionMethod = ZipEntry::kCompressStored;
//                if (inputFp) rewind(inputFp);
//                fseek(mZipFp, startPosn, SEEK_SET);
//                /* fall through to kCompressStored case */
//            }
//        }
//        /* handle "no compression" request, or failed compression from above */
//        if (compressionMethod == ZipEntry::kCompressStored) {
//            if (inputFp) {
//                result = copyFpToFp(mZipFp, inputFp, &crc);
//            } else {
//                result = copyDataToFp(mZipFp, data, size, &crc);
//            }
//            if (result != NO_ERROR) {
//                // don't need to truncate; happens in CDE rewrite
//                ALOGD("failed copying data in\n");
//                goto bail;
//            }
//        }
//
//        // currently seeked to end of file
//        uncompressedLen = inputFp ? ftell(inputFp) : size;
//    } else if (sourceType == ZipEntry::kCompressDeflated) {
//        /* we should support uncompressed-from-compressed, but it's not
//         * important right now */
//        assert(compressionMethod == ZipEntry::kCompressDeflated);
//
//        bool scanResult;
//        int method;
//        long compressedLen;
//
//        scanResult = ZipUtils::examineGzip(inputFp, &method, &uncompressedLen,
//                        &compressedLen, &crc);
//        if (!scanResult || method != ZipEntry::kCompressDeflated) {
//            ALOGD("this isn't a deflated gzip file?");
//            result = (status_t)UNKNOWN_ERROR;
//            goto bail;
//        }
//
//        result = copyPartialFpToFp(mZipFp, inputFp, compressedLen, NULL);
//        if (result != NO_ERROR) {
//            ALOGD("failed copying gzip data in\n");
//            goto bail;
//        }
//    } else {
//        assert(false);
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    /*
//     * We could write the "Data Descriptor", but there doesn't seem to
//     * be any point since we're going to go back and write the LFH.
//     *
//     * Update file offsets.
//     */
//    endPosn = ftell(mZipFp);            // seeked to end of compressed data
//
//    /*
//     * Success!  Fill out new values.
//     */
//    pEntry->setDataInfo(uncompressedLen, endPosn - startPosn, crc,
//        compressionMethod);
//    modWhen = getModTime(inputFp ? fileno(inputFp) : fileno(mZipFp));
//    pEntry->setModWhen(modWhen);
//    pEntry->setLFHOffset(lfhPosn);
//    mEOCD.mNumEntries++;
//    mEOCD.mTotalNumEntries++;
//    mEOCD.mCentralDirSize = 0;      // mark invalid; set by flush()
//    mEOCD.mCentralDirOffset = endPosn;
//
//    /*
//     * Go back and write the LFH.
//     */
//    if (fseek(mZipFp, lfhPosn, SEEK_SET) != 0) {
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//    pEntry->mLFH.write(mZipFp);
//
//    /*
//     * Add pEntry to the list.
//     */
//    mEntries.add(pEntry);
//    if (ppEntry != NULL)
//        *ppEntry = pEntry;
//    pEntry = NULL;
//
//bail:
//    if (inputFp != NULL)
//        fclose(inputFp);
//    delete pEntry;
//    return result;
//}
//
///*
// * Add an entry by copying it from another zip file.  If "padding" is
// * nonzero, the specified number of bytes will be added to the "extra"
// * field in the header.
// *
// * If "ppEntry" is non-NULL, a pointer to the new entry will be returned.
// */
//status_t ZipFile::add(const ZipFile* pSourceZip, const ZipEntry* pSourceEntry,
//    int padding, ZipEntry** ppEntry)
//{
//    ZipEntry* pEntry = NULL;
//    status_t result;
//    long lfhPosn, endPosn;
//
//    if (mReadOnly)
//        return INVALID_OPERATION;
//
//    /* make sure we're in a reasonable state */
//    assert(mZipFp != NULL);
//    assert(mEntries.size() == mEOCD.mTotalNumEntries);
//
//    if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    pEntry = new ZipEntry;
//    if (pEntry == NULL) {
//        result = NO_MEMORY;
//        goto bail;
//    }
//
//    result = pEntry->initFromExternal(pSourceZip, pSourceEntry);
//    if (result != NO_ERROR)
//        goto bail;
//    if (padding != 0) {
//        result = pEntry->addPadding(padding);
//        if (result != NO_ERROR)
//            goto bail;
//    }
//
//    /*
//     * From here on out, failures are more interesting.
//     */
//    mNeedCDRewrite = true;
//
//    /*
//     * Write the LFH.  Since we're not recompressing the data, we already
//     * have all of the fields filled out.
//     */
//    lfhPosn = ftell(mZipFp);
//    pEntry->mLFH.write(mZipFp);
//
//    /*
//     * Copy the data over.
//     *
//     * If the "has data descriptor" flag is set, we want to copy the DD
//     * fields as well.  This is a fixed-size area immediately following
//     * the data.
//     */
//    if (fseek(pSourceZip->mZipFp, pSourceEntry->getFileOffset(), SEEK_SET) != 0)
//    {
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    off_t copyLen;
//    copyLen = pSourceEntry->getCompressedLen();
//    if ((pSourceEntry->mLFH.mGPBitFlag & ZipEntry::kUsesDataDescr) != 0)
//        copyLen += ZipEntry::kDataDescriptorLen;
//
//    if (copyPartialFpToFp(mZipFp, pSourceZip->mZipFp, copyLen, NULL)
//        != NO_ERROR)
//    {
//        ALOGW("copy of '%s' failed\n", pEntry->mCDE.mFileName);
//        result = (status_t)UNKNOWN_ERROR;
//        goto bail;
//    }
//
//    /*
//     * Update file offsets.
//     */
//    endPosn = ftell(mZipFp);
//
//    /*
//     * Success!  Fill out new values.
//     */
//    pEntry->setLFHOffset(lfhPosn);      // sets mCDE.mLocalHeaderRelOffset
//    mEOCD.mNumEntries++;
//    mEOCD.mTotalNumEntries++;
//    mEOCD.mCentralDirSize = 0;      // mark invalid; set by flush()
//    mEOCD.mCentralDirOffset = endPosn;
//
//    /*
//     * Add pEntry to the list.
//     */
//    mEntries.add(pEntry);
//    if (ppEntry != NULL)
//        *ppEntry = pEntry;
//    pEntry = NULL;
//
//    result = NO_ERROR;
//
//bail:
//    delete pEntry;
//    return result;
//}
//
///*
// * Copy all of the bytes in "src" to "dst".
// *
// * On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
// * will be seeked immediately past the data.
// */
//status_t ZipFile::copyFpToFp(FILE* dstFp, FILE* srcFp, unsigned long* pCRC32)
//{
//    unsigned char tmpBuf[32768];
//    size_t count;
//
//    *pCRC32 = crc32(0L, Z_NULL, 0);
//
//    while (1) {
//        count = fread(tmpBuf, 1, sizeof(tmpBuf), srcFp);
//        if (ferror(srcFp) || ferror(dstFp))
//            return errnoToStatus(errno);
//        if (count == 0)
//            break;
//
//        *pCRC32 = crc32(*pCRC32, tmpBuf, count);
//
//        if (fwrite(tmpBuf, 1, count, dstFp) != count) {
//            ALOGD("fwrite %d bytes failed\n", (int) count);
//            return (status_t)UNKNOWN_ERROR;
//        }
//    }
//
//    return NO_ERROR;
//}
//
///*
// * Copy all of the bytes in "src" to "dst".
// *
// * On exit, "dstFp" will be seeked immediately past the data.
// */
//status_t ZipFile::copyDataToFp(FILE* dstFp,
//    const void* data, size_t size, unsigned long* pCRC32)
//{
//    size_t count;
//
//    *pCRC32 = crc32(0L, Z_NULL, 0);
//    if (size > 0) {
//        *pCRC32 = crc32(*pCRC32, (const unsigned char*)data, size);
//        if (fwrite(data, 1, size, dstFp) != size) {
//            ALOGD("fwrite %d bytes failed\n", (int) size);
//            return (status_t)UNKNOWN_ERROR;
//        }
//    }
//
//    return NO_ERROR;
//}
//
///*
// * Copy some of the bytes in "src" to "dst".
// *
// * If "pCRC32" is NULL, the CRC will not be computed.
// *
// * On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
// * will be seeked immediately past the data just written.
// */
//status_t ZipFile::copyPartialFpToFp(FILE* dstFp, FILE* srcFp, long length,
//    unsigned long* pCRC32)
//{
//    unsigned char tmpBuf[32768];
//    size_t count;
//
//    if (pCRC32 != NULL)
//        *pCRC32 = crc32(0L, Z_NULL, 0);
//
//    while (length) {
//        long readSize;
//        
//        readSize = sizeof(tmpBuf);
//        if (readSize > length)
//            readSize = length;
//
//        count = fread(tmpBuf, 1, readSize, srcFp);
//        if ((long) count != readSize) {     // error or unexpected EOF
//            ALOGD("fread %d bytes failed\n", (int) readSize);
//            return (status_t)UNKNOWN_ERROR;
//        }
//
//        if (pCRC32 != NULL)
//            *pCRC32 = crc32(*pCRC32, tmpBuf, count);
//
//        if (fwrite(tmpBuf, 1, count, dstFp) != count) {
//            ALOGD("fwrite %d bytes failed\n", (int) count);
//            return (status_t)UNKNOWN_ERROR;
//        }
//
//        length -= readSize;
//    }
//
//    return NO_ERROR;
//}
//
///*
// * Compress all of the data in "srcFp" and write it to "dstFp".
// *
// * On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
// * will be seeked immediately past the compressed data.
// */
//status_t ZipFile::compressFpToFp(FILE* dstFp, FILE* srcFp,
//    const void* data, size_t size, unsigned long* pCRC32)
//{
//    status_t result = NO_ERROR;
//    const size_t kBufSize = 32768;
//    unsigned char* inBuf = NULL;
//    unsigned char* outBuf = NULL;
//    z_stream zstream;
//    bool atEof = false;     // no feof() aviailable yet
//    unsigned long crc;
//    int zerr;
//
//    /*
//     * Create an input buffer and an output buffer.
//     */
//    inBuf = new unsigned char[kBufSize];
//    outBuf = new unsigned char[kBufSize];
//    if (inBuf == NULL || outBuf == NULL) {
//        result = NO_MEMORY;
//        goto bail;
//    }
//
//    /*
//     * Initialize the zlib stream.
//     */
//    memset(&zstream, 0, sizeof(zstream));
//    zstream.zalloc = Z_NULL;
//    zstream.zfree = Z_NULL;
//    zstream.opaque = Z_NULL;
//    zstream.next_in = NULL;
//    zstream.avail_in = 0;
//    zstream.next_out = outBuf;
//    zstream.avail_out = kBufSize;
//    zstream.data_type = Z_UNKNOWN;
//
//    zerr = deflateInit2(&zstream, Z_BEST_COMPRESSION,
//        Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
//    if (zerr != Z_OK) {
//        result = (status_t)UNKNOWN_ERROR;
//        if (zerr == Z_VERSION_ERROR) {
//            ALOGE("Installed zlib is not compatible with linked version (%s)\n",
//                ZLIB_VERSION);
//        } else {
//            ALOGD("Call to deflateInit2 failed (zerr=%d)\n", zerr);
//        }
//        goto bail;
//    }
//
//    crc = crc32(0L, Z_NULL, 0);
//
//    /*
//     * Loop while we have data.
//     */
//    do {
//        size_t getSize;
//        int flush;
//
//        /* only read if the input buffer is empty */
//        if (zstream.avail_in == 0 && !atEof) {
//            ALOGV("+++ reading %d bytes\n", (int)kBufSize);
//            if (data) {
//                getSize = size > kBufSize ? kBufSize : size;
//                memcpy(inBuf, data, getSize);
//                data = ((const char*)data) + getSize;
//                size -= getSize;
//            } else {
//                getSize = fread(inBuf, 1, kBufSize, srcFp);
//                if (ferror(srcFp)) {
//                    ALOGD("deflate read failed (errno=%d)\n", errno);
//                    goto z_bail;
//                }
//            }
//            if (getSize < kBufSize) {
//                ALOGV("+++  got %d bytes, EOF reached\n",
//                    (int)getSize);
//                atEof = true;
//            }
//
//            crc = crc32(crc, inBuf, getSize);
//
//            zstream.next_in = inBuf;
//            zstream.avail_in = getSize;
//        }
//
//        if (atEof)
//            flush = Z_FINISH;       /* tell zlib that we're done */
//        else
//            flush = Z_NO_FLUSH;     /* more to come! */
//
//        zerr = deflate(&zstream, flush);
//        if (zerr != Z_OK && zerr != Z_STREAM_END) {
//            ALOGD("zlib deflate call failed (zerr=%d)\n", zerr);
//            result = (status_t)UNKNOWN_ERROR;
//            goto z_bail;
//        }
//
//        /* write when we're full or when we're done */
//        if (zstream.avail_out == 0 ||
//            (zerr == Z_STREAM_END && zstream.avail_out != (uInt) kBufSize))
//        {
//            ALOGV("+++ writing %d bytes\n", (int) (zstream.next_out - outBuf));
//            if (fwrite(outBuf, 1, zstream.next_out - outBuf, dstFp) !=
//                (size_t)(zstream.next_out - outBuf))
//            {
//                ALOGD("write %d failed in deflate\n",
//                    (int) (zstream.next_out - outBuf));
//                goto z_bail;
//            }
//
//            zstream.next_out = outBuf;
//            zstream.avail_out = kBufSize;
//        }
//    } while (zerr == Z_OK);
//
//    assert(zerr == Z_STREAM_END);       /* other errors should've been caught */
//
//    *pCRC32 = crc;
//
//z_bail:
//    deflateEnd(&zstream);        /* free up any allocated structures */
//
//bail:
//    delete[] inBuf;
//    delete[] outBuf;
//
//    return result;
//}
//
///*
// * Mark an entry as deleted.
// *
// * We will eventually need to crunch the file down, but if several files
// * are being removed (perhaps as part of an "update" process) we can make
// * things considerably faster by deferring the removal to "flush" time.
// */
//status_t ZipFile::remove(ZipEntry* pEntry)
//{
//    /*
//     * Should verify that pEntry is actually part of this archive, and
//     * not some stray ZipEntry from a different file.
//     */
//
//    /* mark entry as deleted, and mark archive as dirty */
//    pEntry->setDeleted();
//    mNeedCDRewrite = true;
//    return NO_ERROR;
//}
//
///*
// * Flush any pending writes.
// *
// * In particular, this will crunch out deleted entries, and write the
// * Central Directory and EOCD if we have stomped on them.
// */
//status_t ZipFile::flush(void)
//{
//    status_t result = NO_ERROR;
//    long eocdPosn;
//    int i, count;
//
//    if (mReadOnly)
//        return INVALID_OPERATION;
//    if (!mNeedCDRewrite)
//        return NO_ERROR;
//
//    assert(mZipFp != NULL);
//
//    result = crunchArchive();
//    if (result != NO_ERROR)
//        return result;
//
//    if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0)
//        return (status_t)UNKNOWN_ERROR;
//
//    count = mEntries.size();
//    for (i = 0; i < count; i++) {
//        ZipEntry* pEntry = mEntries[i];
//        pEntry->mCDE.write(mZipFp);
//    }
//
//    eocdPosn = ftell(mZipFp);
//    mEOCD.mCentralDirSize = eocdPosn - mEOCD.mCentralDirOffset;
//
//    mEOCD.write(mZipFp);
//
//    /*
//     * If we had some stuff bloat up during compression and get replaced
//     * with plain files, or if we deleted some entries, there's a lot
//     * of wasted space at the end of the file.  Remove it now.
//     */
//    if (ftruncate(fileno(mZipFp), ftell(mZipFp)) != 0) {
//        ALOGW("ftruncate failed %ld: %s\n", ftell(mZipFp), strerror(errno));
//        // not fatal
//    }
//
//    /* should we clear the "newly added" flag in all entries now? */
//
//    mNeedCDRewrite = false;
//    return NO_ERROR;
//}
//
///*
// * Crunch deleted files out of an archive by shifting the later files down.
// *
// * Because we're not using a temp file, we do the operation inside the
// * current file.
// */
//status_t ZipFile::crunchArchive(void)
//{
//    status_t result = NO_ERROR;
//    int i, count;
//    long delCount, adjust;
//
//#if 0
//    printf("CONTENTS:\n");
//    for (i = 0; i < (int) mEntries.size(); i++) {
//        printf(" %d: lfhOff=%ld del=%d\n",
//            i, mEntries[i]->getLFHOffset(), mEntries[i]->getDeleted());
//    }
//    printf("  END is %ld\n", (long) mEOCD.mCentralDirOffset);
//#endif
//
//    /*
//     * Roll through the set of files, shifting them as appropriate.  We
//     * could probably get a slight performance improvement by sliding
//     * multiple files down at once (because we could use larger reads
//     * when operating on batches of small files), but it's not that useful.
//     */
//    count = mEntries.size();
//    delCount = adjust = 0;
//    for (i = 0; i < count; i++) {
//        ZipEntry* pEntry = mEntries[i];
//        long span;
//
//        if (pEntry->getLFHOffset() != 0) {
//            long nextOffset;
//
//            /* Get the length of this entry by finding the offset
//             * of the next entry.  Directory entries don't have
//             * file offsets, so we need to find the next non-directory
//             * entry.
//             */
//            nextOffset = 0;
//            for (int ii = i+1; nextOffset == 0 && ii < count; ii++)
//                nextOffset = mEntries[ii]->getLFHOffset();
//            if (nextOffset == 0)
//                nextOffset = mEOCD.mCentralDirOffset;
//            span = nextOffset - pEntry->getLFHOffset();
//
//            assert(span >= ZipEntry::LocalFileHeader::kLFHLen);
//        } else {
//            /* This is a directory entry.  It doesn't have
//             * any actual file contents, so there's no need to
//             * move anything.
//             */
//            span = 0;
//        }
//
//        //printf("+++ %d: off=%ld span=%ld del=%d [count=%d]\n",
//        //    i, pEntry->getLFHOffset(), span, pEntry->getDeleted(), count);
//
//        if (pEntry->getDeleted()) {
//            adjust += span;
//            delCount++;
//
//            delete pEntry;
//            mEntries.removeAt(i);
//
//            /* adjust loop control */
//            count--;
//            i--;
//        } else if (span != 0 && adjust > 0) {
//            /* shuffle this entry back */
//            //printf("+++ Shuffling '%s' back %ld\n",
//            //    pEntry->getFileName(), adjust);
//            result = filemove(mZipFp, pEntry->getLFHOffset() - adjust,
//                        pEntry->getLFHOffset(), span);
//            if (result != NO_ERROR) {
//                /* this is why you use a temp file */
//                ALOGE("error during crunch - archive is toast\n");
//                return result;
//            }
//
//            pEntry->setLFHOffset(pEntry->getLFHOffset() - adjust);
//        }
//    }
//
//    /*
//     * Fix EOCD info.  We have to wait until the end to do some of this
//     * because we use mCentralDirOffset to determine "span" for the
//     * last entry.
//     */
//    mEOCD.mCentralDirOffset -= adjust;
//    mEOCD.mNumEntries -= delCount;
//    mEOCD.mTotalNumEntries -= delCount;
//    mEOCD.mCentralDirSize = 0;  // mark invalid; set by flush()
//
//    assert(mEOCD.mNumEntries == mEOCD.mTotalNumEntries);
//    assert(mEOCD.mNumEntries == count);
//
//    return result;
//}
//
///*
// * Works like memmove(), but on pieces of a file.
// */
//status_t ZipFile::filemove(FILE* fp, off_t dst, off_t src, size_t n)
//{
//    if (dst == src || n <= 0)
//        return NO_ERROR;
//
//    unsigned char readBuf[32768];
//
//    if (dst < src) {
//        /* shift stuff toward start of file; must read from start */
//        while (n != 0) {
//            size_t getSize = sizeof(readBuf);
//            if (getSize > n)
//                getSize = n;
//
//            if (fseek(fp, (long) src, SEEK_SET) != 0) {
//                ALOGD("filemove src seek %ld failed\n", (long) src);
//                return (status_t)UNKNOWN_ERROR;
//            }
//
//            if (fread(readBuf, 1, getSize, fp) != getSize) {
//                ALOGD("filemove read %ld off=%ld failed\n",
//                    (long) getSize, (long) src);
//                return (status_t)UNKNOWN_ERROR;
//            }
//
//            if (fseek(fp, (long) dst, SEEK_SET) != 0) {
//                ALOGD("filemove dst seek %ld failed\n", (long) dst);
//                return (status_t)UNKNOWN_ERROR;
//            }
//
//            if (fwrite(readBuf, 1, getSize, fp) != getSize) {
//                ALOGD("filemove write %ld off=%ld failed\n",
//                    (long) getSize, (long) dst);
//                return (status_t)UNKNOWN_ERROR;
//            }
//
//            src += getSize;
//            dst += getSize;
//            n -= getSize;
//        }
//    } else {
//        /* shift stuff toward end of file; must read from end */
//        assert(false);      // write this someday, maybe
//        return (status_t)UNKNOWN_ERROR;
//    }
//
//    return NO_ERROR;
//}
//
//
///*
// * Get the modification time from a file descriptor.
// */
//time_t ZipFile::getModTime(int fd)
//{
//    struct stat sb;
//
//    if (fstat(fd, &sb) < 0) {
//        ALOGD("HEY: fstat on fd %d failed\n", fd);
//        return (time_t) -1;
//    }
//
//    return sb.st_mtime;
//}
//
//
//#if 0       /* this is a bad idea */
///*
// * Get a copy of the Zip file descriptor.
// *
// * We don't allow this if the file was opened read-write because we tend
// * to leave the file contents in an uncertain state between calls to
// * flush().  The duplicated file descriptor should only be valid for reads.
// */
//int ZipFile::getZipFd(void) const
//{
//    if (!mReadOnly)
//        return INVALID_OPERATION;
//    assert(mZipFp != NULL);
//
//    int fd;
//    fd = dup(fileno(mZipFp));
//    if (fd < 0) {
//        ALOGD("didn't work, errno=%d\n", errno);
//    }
//
//    return fd;
//}
//#endif
//
//
//#if 0
///*
// * Expand data.
// */
//bool ZipFile::uncompress(const ZipEntry* pEntry, void* buf) const
//{
//    return false;
//}
//#endif
//
//// free the memory when you're done
//void* ZipFile::uncompress(const ZipEntry* entry)
//{
//    size_t unlen = entry->getUncompressedLen();
//    size_t clen = entry->getCompressedLen();
//
//    void* buf = malloc(unlen);
//    if (buf == NULL) {
//        return NULL;
//    }
//
//    fseek(mZipFp, 0, SEEK_SET);
//
//    off_t offset = entry->getFileOffset();
//    if (fseek(mZipFp, offset, SEEK_SET) != 0) {
//        goto bail;
//    }
//
//    switch (entry->getCompressionMethod())
//    {
//        case ZipEntry::kCompressStored: {
//            ssize_t amt = fread(buf, 1, unlen, mZipFp);
//            if (amt != (ssize_t)unlen) {
//                goto bail;
//            }
//#if 0
//            printf("data...\n");
//            const unsigned char* p = (unsigned char*)buf;
//            const unsigned char* end = p+unlen;
//            for (int i=0; i<32 && p < end; i++) {
//                printf("0x%08x ", (int)(offset+(i*0x10)));
//                for (int j=0; j<0x10 && p < end; j++) {
//                    printf(" %02x", *p);
//                    p++;
//                }
//                printf("\n");
//            }
//#endif
//
//            }
//            break;
//        case ZipEntry::kCompressDeflated: {
//            if (!ZipUtils::inflateToBuffer(mZipFp, buf, unlen, clen)) {
//                goto bail;
//            }
//            }
//            break;
//        default:
//            goto bail;
//    }
//    return buf;
//
//bail:
//    free(buf);
//    return NULL;
//}


/*
 * ===========================================================================
 *      EndOfCentralDir
 * ===========================================================================
 */

/*
 * Read the end-of-central-dir fields.
 *
 * "buf" should be positioned at the EOCD signature, and should contain
 * the entire EOCD area including the comment.
 */
status_t EndOfCentralDir::readBuf(const unsigned char* buf, int len)
{
    /* don't allow re-use */
    assert(mComment == NULL);

    if (len < kEOCDLen) {
        /* looks like ZIP file got truncated */
        ALOGD(" Zip EOCD: expected >= %d bytes, found %d\n",
            kEOCDLen, len);
        return INVALID_OPERATION;
    }

    /* this should probably be an assert() */
    if (ZipEntry::getLongLE(&buf[0x00]) != kSignature)
        return (status_t)UNKNOWN_ERROR;

    mDiskNumber = ZipEntry::getShortLE(&buf[0x04]);
    mDiskWithCentralDir = ZipEntry::getShortLE(&buf[0x06]);
    mNumEntries = ZipEntry::getShortLE(&buf[0x08]);
    mTotalNumEntries = ZipEntry::getShortLE(&buf[0x0a]);
    mCentralDirSize = ZipEntry::getLongLE(&buf[0x0c]);
    mCentralDirOffset = ZipEntry::getLongLE(&buf[0x10]);
    mCommentLen = ZipEntry::getShortLE(&buf[0x14]);

    // TODO: validate mCentralDirOffset

    if (mCommentLen > 0) {
        if (kEOCDLen + mCommentLen > len) {
            ALOGD("EOCD(%d) + comment(%d) exceeds len (%d)\n",
                kEOCDLen, mCommentLen, len);
            return (status_t)UNKNOWN_ERROR;
        }
        mComment = new unsigned char[mCommentLen];
        memcpy(mComment, buf + kEOCDLen, mCommentLen);
    }

    return NO_ERROR;
}

/*
 * Write an end-of-central-directory section.
 */
status_t EndOfCentralDir::write(FILE* fp)
{
    unsigned char buf[kEOCDLen];

    ZipEntry::putLongLE(&buf[0x00], kSignature);
    ZipEntry::putShortLE(&buf[0x04], mDiskNumber);
    ZipEntry::putShortLE(&buf[0x06], mDiskWithCentralDir);
    ZipEntry::putShortLE(&buf[0x08], mNumEntries);
    ZipEntry::putShortLE(&buf[0x0a], mTotalNumEntries);
    ZipEntry::putLongLE(&buf[0x0c], mCentralDirSize);
    ZipEntry::putLongLE(&buf[0x10], mCentralDirOffset);
    ZipEntry::putShortLE(&buf[0x14], mCommentLen);

    if (fwrite(buf, 1, kEOCDLen, fp) != kEOCDLen)
        return (status_t)UNKNOWN_ERROR;
    if (mCommentLen > 0) {
        assert(mComment != NULL);
        if (fwrite(mComment, mCommentLen, 1, fp) != mCommentLen)
            return (status_t)UNKNOWN_ERROR;
    }

    return NO_ERROR;
}

/*
 * Dump the contents of an EndOfCentralDir object.
 */
void EndOfCentralDir::dump(void) const
{
    ALOGD(" EndOfCentralDir contents:\n");
    ALOGD("  diskNum=%u diskWCD=%u numEnt=%u totalNumEnt=%u\n",
        mDiskNumber, mDiskWithCentralDir, mNumEntries, mTotalNumEntries);
    ALOGD("  centDirSize=%lu centDirOff=%lu commentLen=%u\n",
        mCentralDirSize, mCentralDirOffset, mCommentLen);
}

